Mohammad Reza Zare, Ali Fatehizadeh, Mohammad Mehdi Amin, Afshin Ebrahimi, Bijan Bina, Ayat Rahmani, et al . Assessment of the Half Maximal Effective Concentration of Growth Inhibition for Heavy Metals on Bacteria Present in Sequencing Batch Reactors. HSR 2016; 12 (1) :77-83
URL:
http://hsr.mui.ac.ir/article-1-833-en.html
1- Assistant Professor, Department of Environmental Health Engineering, Evaz School of Health, Larestan School of Medical Sciences, Larestan AND Environment Research Center AND School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
2- Assistant Professor, Environment Research Center AND Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
3- Professor, Environment Research Center AND Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
4- Associate Professor, Environment Research Center AND Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
5- Professor, Environment Research Center AND Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran Corresponding Author: Bijan Bina, Email: bbina123@yahoo.com
6- PhD Candidate, Department of Environmental Health Engineering, School of Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
7- Assistant Professor, Department of Environmental Health Engineering, Evaz School of Health, Larestan School of Medical Sciences, Larestan, Iran
8- MSc Student, Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
9- MSc Student, Department of Environmental Health Engineering, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran
Abstract: (674 Views)
Background: Among the chemical pollutants present in wastewater, heavy metals are persistent compounds the toxicity of which on biological wastewater processes, humans, and the environment has been proven in various studies. In this study, the half maximal effective concentration (EC50) of growth inhibition of cadmium, lead, and mercury was assessed on dominant bacterial species present in sequencing batch reactors (SBR).Methods: Biomass sample was obtained from the biological unit of the SBR established in Moorchekhort Industrial Settlement, Isfahan, Iran. After cultivation and isolation of the dominant bacterial species, their DNA was sequenced through polymerase chain reaction (PCR) technique and the bacteria species were determined. After exposure of these bacteria to different concentrations of mercury, cadmium, and lead, their EC50 was determined using resazurin bioassay.Findings: Aeromonas, Pseudomonas, Bacillus, and Enterobacter were registered as the 4 dominant bacterial species in the SBR. A great difference was observed in the sensitivity of these 4 bacteria to the heavy metals. Pseudomonas was the most sensitive bacteria to cadmium and lead, while Aeromonas was the most sensitive specie to lead.Conclusion: It can be concluded that Aeromonas and Pseudomonas are suitable bioindicators for toxicity assessment of wastewater and effluents contaminated with heavy metals.
Type of Study:
Research |
Subject:
education health and promotion Received: 2020/07/16 | Accepted: 2016/04/15 | Published: 2016/04/15